Estimating flexible selling expense budget and computing sales volume variance. Miami Products estimates that it will incur the following selling expenses next period:

Salaries (fixed)	$ 20,000
Commissions (0.05 of sales revenue)	17,875
Travel (0.03 of sales revenue)	10,725
Advertising (fixed).	50,000
Sales Office Costs ($4,000 plus $0.05 per unit sold)	7,250
Shipping Costs ($0.10 per unit sold).	6,500
Total Selling Expenses	$112,350

A. Derive the cost equation for selling expenses. (Hint: y = a + bx + cy.)

B. Assume that Miami sells 50,000 units during the period. Budgeted sales totaled 65,000 units at a budgeted sales price of $5.50 per unit. Prepare a variance report to show the difference between the master budget and the flexible budget.